Composite shaped block

ABSTRACT

The invention relates to a composite shaped block produced by placing a top plate serving as a covering layer onto a supporting body. This supporting body is provided with a binder compound and is produced by a shaping process. The invention also relates to a method for producing composite shaped blocks of this type.

The invention relates to a composite shaped block manufactured byapplying an upper slab, as a covering top layer, to a support elementprovided with an agglomerant and manufactured by means of a shapingprocess, and a method for manufacturing such composite shaped blocks.

Shaped blocks, and particularly paving stones/paving elements, terraceand footpath slabs, are known in a variety of design forms. They areused for landscape gardening and also for strengthening surfaces thatare walked and ridden on.

Natural stones are unique optical materials with long life and highprestige, characteristics which cannot be achieved with industriallyproduced concrete stone or concrete ashlar in the surface. Advantages ofa natural stone include its high aesthetic value, a large variety ofmaterials and the rich selection of colours, structures and qualities.Because of this an increasing number of architects, planners and ownersare tending towards the use of natural stone products, even though theyare much more expensive. However, some natural stone pavings, laid as afloor, suffer from the disadvantage that they form technically inferioruseful surfaces, with lower load carrying capacity, than concrete stonesor ashlars. Moreover, laying can often only be carried out byspecialists, and not by machine. The following may therefore bementioned as disadvantages: the high material and labour costs and theskill required to process the natural stone correctly, which in manycases cannot be found.

Concrete ashlars are manufactured from cement, quartz sand andadditives. They are produced industrially and can be manufactured in anydesired in any desired shape, at low cost, in large quantities and withlow production tolerances. They have the advantage over sawn,smooth-walled natural stones that the flank surfaces (lateral surfaces)and laying side (base side) are rough because of the production process,which makes for better “grip” in the laying bed and when pointing.Because the material thickness and joint geometry are varied, they maybe designed for high surface loads. Concrete stones or concrete ashlarscan be laid easily and quickly by machine or by temporary workers andhandymen. Due to the above-mentioned characteristics optimum technicaluseful surfaces can be manufactured at low cost, even for the highestloads, in contrast to the natural stone product.

One drawback, however, is that the desired natural stone optics are notgenerally achieved satisfactorily by structuring and colouring theconcrete stone or concrete ashlar surfaces. Unlike natural stoneproducts, the surfaces soil very quickly, or at least more quickly inmost cases, and therefore have a much shorter service life, often onlyaround 10 to 15 years, depending on use.

These structured concrete elements, e.g. with imitation granitesurfaces, are ground and are available with a rough surface in differentslab, ashlar or column formats in the specialist building trade. Thereappearance is substantially influenced not only by the additives usedbut also by any surface machining carried out. However, natural stonesembedded in the shaped concrete element are also known, e.g. from EP 0566 084-A1.

A composite shaped block produced from a concrete element with atrough-shaped recess and a natural stone slab placed on it, with astepped bottom, is described in EP 0 717 147-A1. The section of thestepped bottom projecting from the edge engages in the trough-shapedrecess. The disadvantage of this is that the natural stone slab must bebevelled in the edge region and must be subjected to anothermaterial-removing machining stage. Such machining stages cannot becarried out with the required precision, which would otherwisenecessitate overdosing the quality of adhesive because it cannot bedetermined exactly. Excess adhesive retards the setting process and, inparticular, makes it difficult to position the natural stone slabprecisely in relation to the concrete element.

Natural stones exhibit a different thermal expansion and waterabsorptivity from concrete. When laid in external areas these materialsare exposed for decades to extreme weathering influences, for instancehigh temperature differences, frost/thawing cycles and permanentdampness. Consequently the adhesive layer of a composite material, e.g.a composite material of natural stone and concrete, must be capable ofpermanently compensating for the flexural tension, shearing andcompressive forces resulting from the different coefficients ofexpansion of both materials and those resulting from the mechanicalloads with continuous elasticity. Furthermore, the adhesive layer mustnot swell by permanent moisture or dampness and lose their adhesivity ifthey are to guarantee a permanent combination of even the most varied ofmaterials over decades.

The object of this invention is to utilise the advantages of a concretematerial, whilst at the same time eliminating its disadvantages, but inparticular to make available shaped blocks with head faces having a highaesthetic value in a rich variety of colours and structures.

This object is achieved by the composite shaped block according to claim1. Advantageous developments and designs of the invention are possibleif the measures referred to in the sub-claims are taken.

The invention relates to a composite shaped block manufactured by theapplication of an upper slab as covering top layer to a support elementprovided with an agglomerant and manufactured by means of a shapingprocess. The upper slab and support element are permanently connected toan agglomerant that is applied in a pasty consistency, preferablycontaining minerals, then solidified, by means of the head face of thesupport element, wherein the head face of the support element ispreferably provided with a peripheral edge, and the head face isstructured in a defined manner for optimum absorption of theagglomerant.

The upper slab is preferably 0.5 to 3 cm thick. Head and base surface ofthe upper slap are preferably plane-parallel all over the surfaces.

The support element is preferably 2 to 16 cm thick, but may also be upto 20 cm thick, for example, and ca be manufactured in a wide variety ofvolumetric expansions, but it should preferably be cuboid in shape,wherein the head and base surface of the support element shouldpreferably form essentially plane-parallel surfaces. The lateral facesshould preferably be aligned approximately perpendicularly to the headface.

The agglomerant forms an intermediate layer which is essentially limitedon the outside by the support element and upper slab on all sides.

The lateral faces of the composite shaped block according to theinvention may exhibit cams (bulges) and also recesses so that the camsof a composite shaped block when laid in the composite engage incorresponding recesses of adjacent composite shaped blocks as lateraloffsets. If corresponding recesses are not provided for this engagement,the cams act as spaces when laying in the composite and as transportprotection.

According to a further embodiment of the invention the support elementis provided in all corners with cams which form an additional support atthe statically weakest point of the upper slab (corner). The camspreferably have a semi-circular shape, in the plan view, act in thecomposite as a spacer for forming a uniform joint, and protect thecorners.

The lateral offsets, in conjunction with the above-mentioned “cornershapes”, may form positive connections which are made two-dimensionallyor by means of inter-locking offset elements, possibly in the form ofpositively interlocking spaces on the lateral walls. Intervals or jointscan be created between the laid paving stones with the aid of thespacers to provide secure wedging or denticulation between the stonesand better drainage of the laid surface.

The cams and the additional recesses provided also facilitate preciselaying in the composite and ensure uniform distances between the joints,a durable joint and additional stability in the paving composite. Thehigh resistance to distortion/tilting is particularly advantageous inthe case road surfaces with high horizontal stresses (gradients, etc.).

The offset provides a better overall connection of the laid surface thanmaterials where no offset is provided. The offset should preferably bedesigned so that it also provides the space for the subsequent joint ofthe laid surface and also acts as transport protection.

The cams may be constructed throughout the height of the support elementand even extend, optionally, beyond the total height of the supportelement in the direction of the upper slab, e.g. 1 to 6 mm, preferably 2to 4 mm, above the total height of the support element, and thenpreferably as a lateral stop and for centring the upper slab. Thesection projecting above the total height should preferably be bevelled,and should preferably be constructed at an angle of 40 to 60° so that itis not visible in the joint pattern. The spacer is angular in shape inthis section which is raised above the support surface, the shorter legof the angular shape preferably lying flat on the upper slab.

The support element preferably exhibits spacers (cams) on the lateralsurfaces. These spaces are arranged vertically at different points ofthe support surface so that the composite shaped blocks can be laid indifferent bonds (for example a stretcher, cross or herringbone bond).The spacers are designed in different thicknesses, widths and shapes,depending on the dimensions of the composite shaped block, its heightand the purpose for which it is being used. The spacers prevent theupper slabs from pushing together both during transport and duringlaying, and ensure that when the blocks are laid, a minimum jointdimension is adhered to and the joints can be expertly filled. Thespacers/cams may also be designed so that they are provided with atheoretical fracture point. This ensures that the desired joint width isproduced during laying, but at the same time it prevents permanentconcrete to concrete contact. Instead the spacers break when loads areexerted on the theoretical fracture point and the joint filling materialtakes over the functions of force transmission and buffer action, asprovided for in the design.

In the position of use the support element forms the lower bearingcourse of the composite shaped block. The support element shouldpreferably consist of concrete but may also be manufactured from othersuitable materials such as plastic, metal, wood, clay/ceramics or hybridmixtures or may be of a sandwich structure.

The support element provides the upper slab with the required breakingstrength and service strength, in particular compressive and flexuraltensile strength, and should be selected so that it is much lessexpensive to produce than the upper slab material in terms of itsmaterial value. The support element is manufactured from a material thatcan be poured, shaken or sprinkled in a shaping process.

The support element may be shaped so that several support elements orcomposite shaped blocks can be stacked one inside the other, which saveson transport and storage costs. Furthermore, the support element can beprovided with cavities in which supply pipes, illuminating / lightingelements and heat carriers can be fitted.

The support element may be shortened on the base side, accurate to onemillimetre, to the required final thickness by sawing, calibration orother machining operations. Different thicknesses of the support elementmay be produced if the upper slabs applied exhibit differentthicknesses.

It is also possible to reinforce the support element on the base side ina final stage to provide the required constant overall height withdifferent upper slab thicknesses, possibly by applying a furtherconcrete course.

However, the support element may also be manufactured from plasticmaterial, in particular from recycled plastic waste material. Thecomposite shaped block, on which it is possible to walk or ride,consisting of a plastic support, intermediate layer and mineral upperslab, is then many times lighter than conventional mineral mouldedelements despite essentially the same technical values in terms ofcompressive strength and flexural tensile strength.

The plastic material used may be manufactured from mixed plasticfractions which are either pre-pelleted as so-called pellets for furtherprocessing or are mixed by means of a so-called impact reactor orotherwise prepared for injection moulding. The core may also be producedfrom sorted or unsorted plastic waste. The different geometric shapes ofthe support element may be produced from “simple” and low cost injectionmouldings, which also makes shaping generally less expensive thanpavings of solid natural stone.

To increase stability generally a suitable counter-moulding is insertedin the base side of the plastic support element to produce a closedlaying surface. This counter-moulding may be produced positively so thatan airtight space is created to provide the insulation action which,assuming corresponding weathering, reduces the formation of frost on thetop of the slab and therefore the risk of accidents, among other things.

Cavities may be heated by suitable measures, for which purpose it ispossible to provide the counter-moulding with heating wires, forexample, or to heat it by other thermal means. The energy required canbe supplied by suitable interconnected plug-in systems, and thepavements can therefore be heated favourably and efficiently. A lightingdevice can be installed in the plastic core, and the core itself,together with the upper slab of a mineral material, can be designed sothat they are translucent.

Because of the geometrical shape of the plastic core it is possible tominimise the thermal expansion of the plastic core.

The finished pavement has considerable advantages over conventionalpavements for greater structural heights (from 3 cm) because it islighter and sawing, drilling and other machining operations can becarried out more easily, with greater cost savings. Furthermore, itfeels more pleasant to walk on than pavements consisting solely ofmineral materials.

Concrete is produced from a mixture of cement, grains of rock—also knownas concrete aggregate—and water, together with other additivesoptionally, by heating the “cement paste” (=cement+water). As “freshmixed concrete”, with an optional consistency range, the concrete can bepoured or shaken/pressed into any shape and structure. The supportelement, after setting, exhibits a compressive strength generallyranging from 25 N/mm² to well over 60 N/mm².

Mixtures of unbroken and/or broken grains of natural and/or artificialmineral substances are used as rock grains, e.g. different sizes ofgrains of sand, gravel, chippings, broken stones, swelling clay orswelling slate (lightweight concrete), slags and/or iron oxide.

Furthermore, conventional additives such as plasticizers, air-entrainingagents, (dye) pigments, concrete densifiers, setting accelerators,setting retardants, stabilisers, liquefiers, fluxes, injection aids,micro- and nanosilica, rock flours, plastic dispersions, fibres and/orchromate reducers may be added.

If cement and water are mixed to form a paste, this paste graduallysolidifies. The cement paste develops into cement block by stiffening(setting) and heating. This solidification relies upon the formation ofwater resistant (hydraulic) compounds.

There are a number of possibilities for densifying the concrete, such asreinforced stamping, stirring and shaking. The support element may alsoconsist of reinforced concrete, i.e. reinforcing inserts (round steel,steel mats, fibres, non-woven fabrics, etc.). Whilst the concreteexhibits compressive strength, the steel or other components mentioned,with greater tensile strength, absorb the tensile stresses that aregenerated.

The volume of the concrete changes as a result of creep, shrinkage andseasonal temperature fluctuations. A structural element 10 m long, forexample, experiences a variation in length of around 10 mm per 100 K oftemperature difference. This also gives rise to tensile and compressivestresses.

The support element exhibits an upper support surface which isconstructed so that it is essentially plane-parallel to the basesurface. The support surface is designed as a structuredthree-dimensional surface, where the structure may take different forms.A common feature of all the surface structures is that they exhibit anouter, convex upper edge along the lateral edges of the support element,and the upper edge forms a support surface that is essentiallyplane-parallel to the base surface.

Moreover, several convex support faces should preferably be provided inthe surface clamped by the outer edge as further contact supports. Theupper edge and the convex partial support faces should preferably form acommon support surface plane-parallel to the base surface. For thispurpose the inner convex partial support faces are designed so that theyare, optionally, slightly higher than the edge support faces, optionallylower, but preferably of the same height. The partial support surfacesmay possibly be pyramidal, hemispherical or conical in shape or, lesspreferably, they may be designed as corrugated, zigzag or groove-shapedelevations. The partial support surfaces form fixing points for theupper slab to be installed and prevent lateral or vertical tilting anddisplacement of the upper slabs. The actual support face of the partialsupport faces preferably has an area of less than 2 cm², in particularless than 1 cm² or even less than 0.5 cm. Limited by the edge, at least4, preferably over 12 partial support faces may be distributed over thetrough-shaped recess. The support face is understood to refer to thesurface in contact with the upper slab, including any agglomerantbetween the upper slab and the support face in a thickness of up tothree times the mean granulation of the agglomerant.

Because of the defined structured natured of the surface, a calculablerecess volume and a larger area are provided for adhesion/connection tothe upper slab, and because of the inner support surfaces highershearing, flexural tension and compressive stability is ensured toenable the forces generated by walking and transport to be absorbed andthe different coefficients of expansion of the materials to be used tobe taken into consideration as far as possible.

The height of the partial support surfaces and their geometry enable thevolume of adhesive to be applied to be calculated and preventagglomerant surpluses so that agglomerate does not escape in anundefined manner from the lateral faces when the upper slab is placed onthe head face of the upper element, and when there is neverthelessuniform distribution in the trough-shaped recess, in which case thepartial support faces must also be provided with agglomerant when it isapplied.

In addition, because of the small contact area and the large number ofsupport faces an accelerated setting process is deliberately initiatedat the tips of the partial support faces, which process ensuresimmediate fixing of the upper slab installed. This guarantees that thecomposite block can be transported and further machined immediatelyafter the upper slabs are installed without the upper slabs beingdisplaced from the defined point of contact as the working processcontinues or being loosened from the composite.

Unlike the methods of prior art, the aforementioned characteristicsprovide the possibility of producing a composite shaped block on anindustrial scale in the cycled production process, and also ofcalculating exactly the volume of adhesive to be applied. The partialsupport faces also enable the composite blocks to be stacked without theagglomerant having to set completely.

However, the peripheral outer edge of the support surface also be openedaccording to a further embodiment so that the agglomerant can bedischarged at a defined point. The openings may possibly exhibitpenetration areas of the order of 0.2 to 1 cm². The support elementshould preferably only exhibit 1 to 6, in particular 1 to 3 openings oneach of its lateral faces.

The partial support faces may also be subsequently applied to thesurface outside the production process of the support element orinstalled in the support element and exhibit the same geometries asdescribed above.

The coat thickness of the agglomerant should preferably be on average 2to 12 mm, and in particular preference 2 to 5 mm.

It is also possible to provide the support element with further cavitiesextending from the head face in the direction of the base surface,preferably to a depth of ⅔ of the total thickness of the supportelement. The cavities serve to save material and weight and also receiveexcess agglomerant, which has a positive influence on the adhesivejoint. For example, the total volume of all the recesses/cavities mayconstitute 5 to 75% of the total volume of the support element.

The other cavities extending in the direction of the base surface may beshaped so that they widen in diameter as they extend downwards,resulting in an upward penetration of the agglomerant, causing it toform a paste at the bottom and wedge tight after setting.

Furthermore, cavities in the shape of troughs are installed inparticular preference in the trough-shaped recess. The volume of thetroughs may, for example, range from the same volume as the partialsupport faces up to 50%, preferably 5 to 15% less than this volume.

It is also preferred if the troughs are distributed in the same field asthat of the elevation, i.e. each partial support face exhibits anaverage of at least half a trough, adjacent to it, in order to shortenthe path of the agglomerant when the upper slab is installed. Theadjacent trough preferably has 0.2 to 1 times the volume of the partialsupport face.

The cavities, particularly those extending from the head face to thebase face, should preferably not be completely filled with agglomerant,so that cavities are left which act as a buffer against thermal materialexpansion.

In the process of manufacturing the support elements the surfacegeometry of the support face of the support element, including thecavities extending in the direction of the base face, may simply bedetermined by the type of top ram used. Optionally, two top rams areused, one for forming the cavities extending to the base face and one,preferably after the first, for forming the structured support face. Thesupport element provided with further cavities enables weight andmaterial savings to be made, unlike the solid element. Such a supportelement may also be used solely as a paving stone.

The upper slab, as the top covering layer, may consist of fine vitrifiedclay, ceramic and/or natural stone, as well as other materials such asglass, wood, rubber, metal etc. It should preferably be cuboid in shape.

The upper slab, particularly one of materials with finished shapes, mayexhibit different geometric shapes for engaging with the bindingadditive and support element on the base head side, the base sidepreferably being planar in design and, optionally, exhibiting a certainroughness.

The connecting surface may also be machined by mechanical roughening,such as bush-hammering, blasting, chiselling, milling, planning etc. toachieve an enlarged adhesion area.

Natural stones include, of course, stones produced from different basiccomponents such as limestone, dolomite, sandstone etc. Suitable naturalstone materials include: vulcanites such as granite, syrenite, diorite,gabbro, basalt, diabase, rhyolite, trachyte, sedimentites such aspsephites, conglomerates, breccia, sand rocks including the limesandstones, slate, travertine, dolomite stone and shell marl, as well asmetamorphites such as orthogneiss, quartzite, mica slate, phyllites andparagneisses.

Granite is one of the most commonly known and important plutonic rocks,and consists of feldspar, quartz (20-40/50%) and mica (0-10%). Micaprovides granite with contrast and ensures a certain schistosity of therock, and feldspar and, in particular, quartz, ensures hardness. Theproportion of feldspar determines the colour of the rock.

“Diamond quartzites” are schistous materials, over 80% of which areavailable in stratum thicknesses of between 1.0 and 2.0 cm, and whoserich deposits can be worked in open-cast mining. Quartzite belongs tothe group of natural stones with the highest degree of hardness. Thenatural stratum thicknesses and roughnesses of the quartzite surfacesrequire no further machining for producing the composite stonesaccording to the invention, and only the normal material cutting need becarried out. On the one hand the surface roughnesses meet all theconditions for a permanent joint, and on the other they provide apermanently slip resistant, hard wearing floor covering surface.

Other natural stone deposits of similar hardness, e.g. granites, canonly be worked by the block method. Granites must be sawn into slabswith diamond or reciprocating frame saws, and both surfaces must bemechanically re-machined for use as an upper slab.

The upper slab should preferably exhibit the following length (longestside) to thickness expansion: greater than 3 to 1, in particular greaterthan 5:1. The slab may be produced by splitting or machining, such assawing.

Fine vitrified clay is a thoroughly sintered, artificially producedceramic product. It is very compact and also exhibits a very lowporosity, from which it derives special mechanical and chemicalproperties, e.g. frost resistance. In other words, it is a product whichcan also be used to advantage for wall and floor coverings in outdoorareas in cold climatic regions. Moreover, fine vitrified clay is highlyresistant to chemicals and detergents, it has a very high abrasionresistance and a high breaking strength. This renders it ideal forsurfaces subject to intense public traffic and in industrial plants. Inaddition to this it is easy to clean.

The search for new finishes has resulted in a number of differenttreatments for the end product, e.g. polishing, which has been givenrise to two different types of product: natural and polished finevitrified clay. The natural type (receives no subsequent treatment afterfiring) has a natural appearance and to some extent even imitates stoneswhich can be found in nature, such as slate, marble, paving stones, etc.In the case of polished vitrified clay the material is polished afterfiring to give it a high gloss and imitate the surface optics ofpolished marble.

The upper slab may be surface refined by the method described inEuropean patent EP 1 124 774 and EP 0 825 917-B1 (corresponding to U.S.Pat. No. 6,167,879). The disclosure content of these rights ofprotection is hereby made the subject of this application by referenceto it.

A dirt repellent, slip resistant surface, which has varied applicationsas a floor and staircase covering, is provided by the special surfacetreatment of the head side of the upper slab, including laser treatmentand, optionally, combined with subsequent impregnation treatment, or byonly one impregnation treatment. Surface treatment may be used, inparticular preference, for natural stone surfaces.

In addition to water and rock grains, the agglomerant contains at leastone binding additive. The binding additive should preferably be anaqueous polymer dispersion, optionally used together with a cementbinding additive. The agglomerant sets through contact with moisture.

Principal components of the agglomerant in terms of weight, afterdrying, are rock grains, e.g. fine sand, particularly quartz sand with agranulation of 0 to 2 mm, particularly 0 to 1.0 mm. Furthermore, acement, possibly Z325 Portland cement, is advantageously added.

The agglomerant is applied to the head side of the support element,preferably flatly or in the form of pasty, in particular pasty flatbeads, and in particular over the entire width of the support face or atdefined points, the head side of the support element exhibiting partialsupport faces and the deposit areas for the agglomerant being limited bythe outer partial support faces. The upper partial support facesadjacent to the lateral faces of the support element can also be coveredwith agglomerant, e.g. adhesive mortar. Expulsion of the agglomerantapplied, when the upper slab as a top covering layer is placed on thesupport element, is prevented/reduced or defined both the accuratecalculation of the volume of the agglomerant ad by the, outer partialsupport faces, where openings are provided for this purpose. As far asthe inner cavity volume formed between the outer partial support facesand plane-parallel sealing face of this edge support is concerned, thevolume of agglomerant applied should preferably be at least equal to theinner volume of the upper cavity (except the cavities extending in thedirection of the foot face) to ensure that a solid adhesive joint isprovided, to the exclusion of concavities.

The agglomerant may also consist of acrylate, one- and two-componentpolyurethane, thermoplastic, duoplastic or epoxy compounds, which mayalso be reactive, for example, depending on the material of the supportelement.

The aqueous polymer dispersion is suspended/dispersed in water andpreferably a polymer which exhibits, in addition to styrene and/orbutadiene units, at least one polar monomer or polar groups, e.g.carboxyl groups, e.g. in the form of acrylate, methacrylate or vinylacetate groups/monomers. For the hydrolysis resistance it is importantfor the polymer to exhibit a carbon chain as a backbone (carbonback-bone) which carries polar side groups.

Vinyl acetate terpolymers in aqueous dispersion, carboxylatedbutadiene-styrene-methacrylate-polymer lattices or polyurethanedispersion are also suitable, for example.

The composite shaped block may exhibit the shapes that are normal in thestate of the art, for example cube, binder or one and a half, doubleblock, prism block, head or mitre shape. The composite shaped blockaccording to the invention is preferably used as a paving element forexternal installations such as footpaths, roadways and terraces and as adouble floor system for interior areas, but can also be used, with itsdescribed advantages, as a facade element. to advantage.

It is laid in the composite as a paving surface on a bed, preferably bythe filling of joints. In addition to normal mineral filling materials,the jointing compounds used may also be those which contain cement,bitumen as agglomerant and/or additions of plastic agglomerants.

A composite of the blocks is influenced by the geometry of the pavingstones, and loosening of individual blocks is prevented by the action oflive loads and forces from traffic. The composite shaped blocksaccording to the invention could possibly be laid in a series,herringbone or twill joint, scalloped arches, diagonal joint, block orparquet joint, cross joint, stretcher joint or in the Roman joint.

In contrast to natural block paving, the composite shaped blockaccording to the invention can be laid on a prepared paving bed and doesnot require a bed in which it is aligned with a paving hammer to correctfor surface smoothness.

The composite shaped blocks according to the invention may also be usedas an outer covering material that can be walked or ridden on formaximum surface loads, and constitute a product which can be laid aseasily as a concrete stone or concrete ashlar. The covering can also beeasily laid by the inexperienced handyman.

The composite shaped block may also be used in exterior and interiorareas as a substitute for concrete ashlar slabs. The total thickness maybe between 2 and 7 cm, according to the application, the upper slabpreferably exhibiting a thickness of less than 1.3 cm.

The composite block slab may also be produced in total thicknesses ofbelow 3 cm for interior areas or for the use of terrace slabs, etc., sothat it can be provided with a fine vitrified clay upper slab, whichcannot yet be produced as a solid material in thicknesses of over 1.5cm, or can only be produced at high technical and financial cost.

A further object of the invention is to provide an industrially useful,cycled mechanical method for manufacturing the composite shaped blocksaccording to the invention. This object is achieved according to theinvention by means of the method characteristics identified in claim 21.Preferred embodiments form the subject of claims 22 to 27.

A defined volume of concrete is prepared on a vibrating table in amoulding frame which corresponds to the support element to be produced,and is compressed by shaking and shaped to the head face by means of adie.

The shaking forces may be applied by a method that is well known inconnection with concrete stone moulding machines, i.e. by shaking themould and/or the die, but preferably by shaking vibrations of thevibrating table and/or by shaking of a superimposed die load. The shapedblock may also be compressed by pressing or stamping using methodsnormally applied in industry.

The support element, here the support face for the upper slab, ispreferably moistened with water before the agglomerant is applied. Apolymer, as defined above (under aqueous polymer dispersion), can beadded to the water in the weight ratio of 1:9 to 1:50, to improve theadhesive action. The polymer is preferably sprayed on using a dosingdevice.

The die contours the head face of the support element and, inparticular, embosses the peripheral edge and the partial support facesby means of recesses in the die, which edge serves as a support face forthe upper slab. If required the further cavities (troughs) extending inthe direction of the base face are produced by the same or another die.For this purpose finger-shaped, cylindrical or tapered pins arepreferably mounted on the die face and are inserted in the concrete massas the die is lowered. They are preferably aligned in the direction ofthe surface perpendicular of the die face.

Shaping may be carried out by raising the moulding frame and/or the die.The die face may be freed from concrete residues adhering to it afterthe stamping process and after a number of stamping operations.

The shaped and dimensionally stable support element is covered on thesurface with a pasty agglomerant, preferably by means of dosing nozzlesunder which the support element is moved through with the trough-shapedhead face facing upwards. The agglomerant is applied flatly to the headface of the support element, preferably omitting the peripheral edge,particularly in an essentially uniform coat thickness, preferablybetween 2 and 5 mm, the application height of the agglomerant exceeding,independently as a further preference, the height of the partial supportfaces of the head face of the support element by no more than approx.0.5 mm.

Before the agglomerant is applied it may be advantageous to moisten thesupport element in order to provide positive support for the subsequentstage of the adhesion. For this purpose the spray water can be mixedwith the polymer of the adhesive binder, preferably in the ratio 20(water) to 1 (polymer). The agglomerant consists of different mineralsubstances (quartz sand, cement), as well as mixing water and a polymeradditive, which are mixed together in a so-called forced mixer beforeapplication to the support element, then transferred from the mixingtank to a storage tank with a slowly rotating agitator for furtherprocessing. During transport of the mixed agglomerant it must not beexcited by pressing or compression for the purpose of separating out thesolids and liquids. This is guaranteed by the combination of suitablepumps and suitably dimensioned transfer pipes, in terms of volume.

The upper slab and support element are then lowered one on top of theother, flush with the lateral faces, and are brought closer togetherpreferably with slight rotation about the axis of approach, or even withlight vibratory movement (vertically) along the axis of approach. Thesupport element is preferably conveyed in cycles to bring together theupper slab and support element. The head face area of the supportelement preferably exceeds that of the base face of the upper slabslightly, e.g. by an average of 0.5 to 2 mm on all sides.

The upper slab can be centred with the support face by previouslymeasuring the support element and positioning it correspondingly on thebasis of the transmitted data.

The upper slab may be guided by a grab, in particular a strainer grab,and stationary roller elements or guided pressure elements can then beused for subsequently fixing or pressing on the upper slab. For fastsetting the composite shaped block may then be subjected to thermaltreatment, preferably by conveying the composite shaped block to a spacewhose temperature is set to 90 to 150° C., ideally to 110 to 130° C.,e.g. a “paternoster” or a “setting tunnel”.

If required, the upper slab can be provided with an impregnating agentwhich penetrates well into the generally highly structured surface. Forthis purpose the impregnating agent is sprayed onto the surface of theupper slab before the slag enters the drying tunnel.

To support this the upper slabs can be heated before being placed on thesupport element, preferably to approx. 30° C. to 45° C., which may alsobe advantageous in terms of the adhesive joint and improve thesubsequent impregnation action, since the impregnating agent soaks muchbetter into a tempered surface. Heating may be carried out, for example,in a stacking/storage device before the upper slab is positioned on thesupport element.

In particular preference an aqueous dispersion of a silicon-organiccompound in water is used as an impregnator. The purpose of such acomposition may also be an additional dispersing aid. However, thesilicon-organic compound may also be absorbed in a hydrocarbon mediumsuch as test petrol. A dispersion of an alkylalkoxy silane and afluorine polymer in water has proved extremely advantageous as animpregnating agent.

However, the impregnating agent may also consist of an aqueousdispersion of an acrylate polymer. The impregnator is preferably appliedby a dosing device, with flat application of theimpregnator/impregnating composition, preferably by spraying. However,it may also be applied by other methods, e.g. rolling.

After the impregnator is applied treatment may also be carried out bythermal heating, microwaves, UV or IR radiation, resulting either inrecrystallisation of the surface in mild temperatures, or fusion of thesilicon-organic compound with the carrier material at high temperatures.According to a preferred design of the invention a limit temperature of75° C., for example, is not exceeded on the surface of the mineralmaterial. The prescribed process can be repeated several times, e.g.there may be a second or third impregnation of the upper slab surface atthe exit of the so-called “drying tunnel”.

An increased adhesive and shearing action can be achieved and a definedsurface geometry can be produced by using a facing as a support face ofthe concrete core, e.g. using natural stone chips. This layer can betempered by additives, e.g. can be provided with water permeability, toguarantee fast drying of the surfaces (after laying and in wetconditions) and to prevent moisture from migrating from the concretecore in or through the adhesive layer or surface.

One advantage over solid natural stone provides the possibility ofsimple shaping of concrete cores—oval, round, angular, includingincisions, all current geometric shapes are cost effective or possible,in any case, unlike solid natural stone. At present geometric shapes,apart from actual shaping, which can be produced with saw blades(straight cuts), can only be achieved with expensive water jet cuttingand only to a depth of approx. 3 to 5 cm (stone-dependent) or by a stonemason. According to the invention the upper slabs may generally be only1 to 2 cm thick, and the support element (concrete core) can be producedcost effectively by shaping to any shape and height.

It is also possible to provide the composite block as a drainage block.By making conical cavities in the support element and correspondingopenings accurately machined in the upper slabs, a useful waterrepellent coat can be produced.

Furthermore, it is possible to provide the upper slabs with luminous ordisplay elements, e.g. by optical fibre cables.

According to a preferred production variant, the support element ismanufactured from “finer” facing concrete, sealed at the top, to obtaina surface that is more dimensionally accurate than conventional concretesurfaces. An “upper concrete”, which offer several advantages, isapplied to the core as the uppermost layer. The upper layer can beproduced to improve the adhesive joint (system in system solution), itcan be made waterproof (faster drying, prevention of water stains,faster thawing in the case of ice and snow) and it can be made moredimensionally accurate, for better design of the troughs or elevations,as opposed to conventional concrete. Small troughs on the highest pointsof the elevations can ensure that the agglomerant forms an extremelythin layer there so that the recesses for receiving transverse forcescan be used immediately after joining. This enables the compositeelements to be stacked immediately after joining without anydisplacement of the cover or top slabs.

The invention is explained in the figures, where:

FIG. 1 shows a plan view of the head face of the support element

FIG. 2 shows the composite shaped block with support element and upperslab along section A in FIG. 1, the cavities (16) lying in plane B alsobeing shown in FIG. 2 for the sake of simplicity. FIG. I shows a planview of the surface shown as C in FIG. 2.

On the lateral faces (9) of the support element (3), the support element(3) exhibits a peripheral edge (11). The edge (11) forms a trough shapeon the head face (4). The upper rim of the edge (11) is designed as anedge face (12) as a surface which is plane-parallel to the base face (8)of the support element (3), the large number of punctiform partialsupport faces (14), together with the edge surface (12), forming thesupport face (13) for the base face (7) of the upper slab (6).

The punctiform partial support faces (14) form part of the pyramidstructure formed on the head face (4). Instead of a pyramid structure,other structures/contours are possible, such as troughs or zigzagenclosures. The pasty agglomerant is deposited in the cavities (17) andis pressed into the remaining volume of the upper cavities (17) afterpositive positioning of the upper slab (2), these cavities beingessentially fully filled. The cavities (16) extending in the directionof the base face (7) only partially absorb agglomerant and serve, amongother things, as a volume buffer for the agglomerant.

By way of example a cam (18) is shown on the lateral wall of thecomposite block, the length of this cam exceeding the height of thelateral face (9) of the support element, but is less than the height ofthe lateral wall (10) of the composite shaped block and lies flush withthe length of the upper slab (2) projecting from the support element.The tip of the cam is chamfered outwardly at an angle of 45°. This is aspecial design. Generally such an excess length is not required.

1. Composite shaped block (1) exhibiting an upper slab (2) as a coveringlayer, and a support element (3) manufactured by a shaping process, withhead face (4), wherein the upper slab (2) and the support element (3)are permanently connected by the head face (4) of the support element,the support element (3) is provided on the head face (4) with a anagglomerant applied and solidified, and the head face (4) of the supportelement (3) is designed in the shape of a trough to receive theagglomerant.
 2. Composite shaped block according to claim 1,characterized in that the upper slab (2) exhibits a thickness of 0.5 to3 cm and, independently of this, the base face (7) of the upper slab (2)forms a planar surface and, in particular, head (6) and base face (7) ofthe upper slab (2) form an essentially plane-parallel surface. 3.Composite shaped block according to claim 1 characterized in that thehead face (4) of the support element (3) stamped so that it istrough-shaped exhibits several convex partial support faces (14) ascontact supports in the surface claimed by the outer edge.
 4. Compositeshaped block according to claim 1 characterized in that the head face(4) stamped in the shape of a trough exhibits partial support faces (14)with supporting faces aligned plane-parallel with the base face (7) ofthe upper slab.
 5. Composite shaped block according to claim 1characterized in that the head face (4) stamped in the face of a troughexhibits partial support faces (14) designed according to one or more ofthe three alternatives: partial support faces (14) are roughly as highas the edge support surface (15), partial support faces (14) arepreferably a maximum of 6 mm, and in particular a maximum of 2 mm higherthan the edge support surface (15), partial support faces (14) are amaximum of 2 mm lower than the edge support surfaces (15).
 6. Compositeshaped block according to claim 1, characterized in that the head face(4) stamped in the shape of trough exhibits partial support face (14),wherein at least 4 of the partial support faces (14) maintain betweenthem at least a distance which is greater than ⅓ of the longest edgedistance, and at least each of the 4 partial support faces (14) lies inone of four coherent partial surfaces of the same size as the troughsurface, and wherein, as a further preference, each of the 4 partialsupport surfaces (14) has a distance of a least ⅓ of the longest edgedistance from the edge (11).
 7. Composite shaped block according toclaim 1 characterized in that the base face (7) of the upper slab (2) issmaller in area than the head face (4) of the support element (3). 8.Composite shaped block according to claim 1 in that the support element(3) exhibits a thickness of 2 to 20 cm and, independently of this, thehead (4) and base face (8) of the support element form essentiallyplane-parallel surfaces.
 9. Composite shaped block according to claim 1characterized in that the set agglomerant forms an intermediate layerbetween support element (3) and upper slab (2), which layer is limitedoutwardly and essentially on all sides by the support element (3) andupper slab (2).
 10. Composite shaped block according to claim 1characterized in that adjacent lateral walls (10) of the compositeshaped block in the region of the corners of the support element exhibitcams (18) which lie at a distance from the lateral walls (1), in theirextent, of at least the length of the excess length of the upper slab(2) in the corner in order to serve as a further support face and/orimpact protection, and in that the cams (18) project preferably by anaverage maximum of 5 mm, preferably a maximum of 3 mm from the surfaceperpendicular on the lateral wall (10).
 11. Composite shaped blockaccording to claim 1 characterized in that the lateral walls (10) of thecomposite shaped block, preferably in the region of the support element(3), exhibit cams (18) or spacers and, optionally, also recesses. 12.Composite shaped block according to claim 1 characterized in that thesupport element (3) forms the lower bearing course of the compositeshaped block (1) in the position of use.
 13. Composite shaped blockaccording to claim 1, characterized in that the support element (3) ismanufactured from a material that can be shaken, sprinkled or is able toflow, by means of a shaping process, and in that the material consistsof plastic, concrete, metal, wood, clay/ceramic or their mixtures,preferably concrete.
 14. Composite shaped block according to claim 1characterized in that the head face (4) of the support element isdesigned to form a support face (13) for the upper slab (2), wherein thehead face (6) exhibits a convex edge running on the outside along theupper edge of the lateral face (9) of the support element, in order toform one or more troughs for receiving the agglomerant, and wherein theupper edge surface (12) forms a support face (13) essentiallyplane-parallel to the base face (8).
 15. Composite shaped blockaccording to claim 1 characterised in that the head face (4) clamps,inside the peripheral convex edge (11), a surface which exhibits severalinner, optionally also punctiform, partial support faces (14) for theupper slab (2), wherein the partial support faces (14) are designed sothat they are no higher than the edge support faces (15), preferably thesame height.
 16. Composite shaped block according to claim 1characterized in that the support element (3) is provided with furthercavities (16) extending from the head face (4) in the direction of thebase face, preferably down to a depth of ⅔ of the total thickness of thesupport element (3), wherein, independently of this, the total volume ofall the recesses/cavities (16, 17) constitutes preferably 5 to 75% ofthe total volume of the support element (3).
 17. Composite shaped blockaccording to claim 1 charactcrised in that the upper slab (2) consistsof fine vitrified clay, ceramic, materials such as glass, wood, rubberetc. and/or natural stone.
 18. Composite shaped block according to claim1 characterised in that in addition to water and rock grains, theagglomerant (5) contains at least one binder, wherein the at least onebinder is an aqueous polymer dispersion which is preferably producedusing styrene and/or butadiene units as monomers, and exhibits a polarmonomer or polar groups, and the binder preferably also incorporates acement and sets on contact with moisture.
 19. Composite shaped blockaccording to claim 1 characterised in that the agglomerant (5) has apasty consistency.
 20. Composite shaped block according to claim 1characterised in that the head face (4) exhibits a trough shape and theperipheral convex edge (11) exhibits openings, preferably 1 to 3openings for the defined discharge of excess agglomerant (5) spacedevery 10 cm of the lateral face of the support element (9).
 21. Methodfor manufacturing composite shaped blocks (1) exhibiting an upper slab(2) as the top covering layer and a support element (3) exhibiting ahead face (4) and manufactured by a shaping process, wherein the upperslab (2) and the support element (3) are permanently connected by thehead face (4) of the support element and the head face (4) of thesupport element has a trough shape for receiving the agglomerant, andwherein the method comprises the following steps: pouring concrete intoa mold frame, corresponding to one or more of the support elements to bemanufactured, trough-shaped contouring of the head face (4) of thesupport element by a negative mold, wherein the negative mold is acontoured die or a contoured base plate of the mold frame, or by amilling process or a drilling process, optionally associated with theinsertion of spacers, application of the pasty agglomerant (5) to thehead face (4) of the support element (3), and aligned, precise bringingtogether of the upper slab (2) and the support face (13) formed by thehead face (4) of the support element.
 22. Method for manufacturingcomposite shaped blocks according to claim 21 characterized in that, inaddition, several cavities (16, 17) extending in the direction of thebase face (7) are produced by the die and/or by shapes in the moldframe, and in that they are introduced or produced preferably by pinsmounted on the die face of by pulling or insert devices on the dieand/or mold frame.
 23. Method for manufacturing composite shaped blocksaccording to claim 21, characterized in that several partial supportfaces (14) extending from the base face (7) are produced by cavities inthe die surface.
 24. Method for manufacturing composite shaped blocksaccording to claim 21 characterized in that the step of applying thepasty agglomerant to the head face (4) of the support element is carriedout by means of dosing nozzles, in particular a slotted nozzle, flatly,preferably in the form of flat beads, or defined points, in particularlyflatly in the form of a cuboid having a height of 2 mm to 5 mm, inparticular 2.5 mm to 3 mm, and/or in that the area peripherally aroundthe edge support faces (15) is smaller than the head face of the supportelement.
 25. Method for manufacturing composite shaped blocks accordingto claim 21 characterized in that the step of installing the upper slab(2) takes place at least in the region of approach where it is broughtinto contact with the pasty agglomerant, with light essentiallyhorizontal backward and forward movement along the axis of approach(vertical vibratory movements), and optionally with additionalhorizontal vibrator movements.
 26. Method for manufacturing compositeshaped blocks according to claim 21 characterized characterized in thatthe step of installing the upper slab (2) is carried out by a grab, inparticular a strainer grab, which preferably also performs the functionsof centering, vibrating with adjustable force and/or pressing with adefined adjustable force.
 27. (canceled)